Hello and welcome to more or less on the BBC World Service, with a program that lies numbers down on a nice black couch, hands them a cup of tea and asks them what they really mean. And I'm Tim Halfard.

The world is understandably dominated by news from Ukraine, and with this news invariably come questions about how we can solve the situation without provoking an even bigger disaster.

So this week we're talking to someone who is a master in the art of negotiation.

Greetings, I'm Barry Nielbuth, I'm a professor at Yale at school of management. I write books. Most recently split the pie, I'm an entrepreneur, I started a company called Honest Tea, which the Englishman doesn't make any sense because it's called tea in a bottle.

Of course more or less wouldn't normally talk to the kind of dangerous radical who doesn't put tea in a cup where it belongs, but Barry really knows what he's talking about when it comes to strategy and negotiations.

In fact, one of his books may have changed my life.

Of all the things you've done Barry, the one that's had the biggest influence on me is that you're the co-author of a book about game theory called Thinking Strategically.

And I think without thinking strategically, I probably wouldn't have decided to become an economist so you've had a huge influence on me personally and I'm delighted that you're able to join us on more or less.

Thank you for inviting me and thank you for those kind words.

I picked Thinking Strategically off the bookshelf not long ago and reread some of it. I have to say Barry, it was a bit of sweet pleasure because I enjoy the book and I enjoy the arguments and the discussions.

But one of the cases that you discuss in detail is the case of nuclear brinkmanship.

And when I first read this case study in 1994, Soviet Union had collapsed and we're talking about Cold War and Isleicism and the Cuban Missile Crisis.

And it just all felt like, oh thank goodness we don't need to worry about that kind of thing anymore.

Of course the reason I reread the book was because the Russian President Vladimir Putin had just raised the nuclear alert level and was baking very thinly veiled threats about using nuclear weapons.

So what does game theory tell us about the use of extreme threats that you would say surely that kind of threat could never be carried out because it would destroy the world?

So let me connect this both to game theory and to negotiation. One of the lessons we talk about in the book is to fight fire with water rather than fight fire with fire.

And to that regard we can be very happy that when President Putin escalated nuclear alerts a level, President Biden did not respond in kind.

He said don't worry relax we're all set we don't have to do anything to escalate as well. And as you point out nobody rationally has an interest in starting a nuclear war that would lead to their own annihilation.

And I don't think that Putin is irrational, but they may take actions which can lead to a probability of war when things escalate out of control.

It's a disheartening situation I think because whenever there is a war it's effectively a negative value negotiation.

I mean this is the kind of way only an economist would put it but people are being killed, properties being destroyed, the pie is shrinking rather than growing.

Do you think that studying game theory and studying economics helps us to refocus on the possibilities of getting into situations where everybody can be better off?

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